Further delineation between typical and atypical dopamine uptake inhibitors: effects on food-maintained behavior and food consumption.

The present studies compared the acute effects of benztropine (BZT) analogs (4-Cl-BZT, JHW 007, AHN 1-055), which are atypical DA uptake inhibitors, with those of the standard DA uptake inhibitors GBR 12909 and cocaine, on the reinforcing efficacy of food and food intake in male Sprague-Dawley rats. Repeated drug effects of JHW 007 on food intake were also determined. The number of ratios completed under a progressive-ratio (PR) schedule of food delivery was used as an index of reinforcing efficacy. Food intake was determined by measuring powdered laboratory-chow consumption during daily 40 min food-availability time periods. Under the PR schedule, cocaine and GBR 12909 dose-dependently increased the number of ratios completed. JHW 007 decreased ratios completed while neither 4-Cl-BZT nor AHN 1-055 increased ratios completed with a magnitude that approximated any of the increases produced by cocaine or GBR 12909. Acute administration of each drug dose-dependently decreased food intake; however, the BZT analogs were more potent than cocaine and GBR 12909. A reduction in food intake emerged after repeated administration of a low dose of JHW 007 indicated that. Future studies that compare JHW 007 to standard anorectic drugs (e.g., phentermine) and continue investigation of the repeated drug effects under similar experimental procedures are clearly warranted.